Various conventional sample analyzers are known, such as multi-item blood cell analyzers, blood coagulation measuring apparatuses, immunoanalyzers, biochemical analyzers, urine analyzers and the like.
Japanese Laid-Open Patent Publication No. H1-161155 discloses an automated analyzer for automatically turning ON a power supply at a preset time, heating a flow cell bath to a predetermined temperature, and automatically performing the operation of a water blank measurement or reagent blank measurement. Japanese Laid-Open Patent Publication No. H1-161155 further discloses a structure which is provided with an automatic cleaning mechanism for injecting a detergent into a pipette and reagent container and automatically performs cleaning operation after the power supply has been turned ON.
Prior to measuring a sample, dirt and air bubbles and the like must be removed since dirt and air bubbles may adhere to the automated analyzer and affect the measurement of the sample. When the automated analyzer performs the cleaning operation, dirt and air bubbles are prevented from influencing the measurement results. However, when a long time elapses since performing a cleaning operation, residual bacteria may breed and new air bubbles may form, thus causing concern that the measurement results may be influenced in such cases. The automated analyzer disclosed in Japanese Laid-Open Patent Publication No. H1-161155 executes a fixed cleaning operation after the power supply has been turned ON regardless of the time that has elapsed since the automated analyzer last performed a cleaning operation. Therefore, there is concern that the cleaning may be inadequate when a long time has elapsed since the previous cleaning.